Manifestations include Angina Pectoris, Acute Myocardial Infarction, Sudden Death
Ischemic Heart Disease
Why does IHD cause Sudden Death?
Likely due to cardiac dysrhythmias
Main risk factors for CAD?
Increasing age, male because estrogen is protective
Ischemic heart disease reflects the presence of _________ in coronary arteries, also known as:
atherosclerosis in coronary arteries = coronary artery disease (CAD)
Moderate risk factors include hypercholesteremia, hypertension, smoking
CAD
Lesser risk factors include diabetes mellitus, obesity, sedentary life style, family history of premature event
CAD
What causes angina pectoris?
An imbalance between coronary blood flow and myocardial oxygen consumption (supply vs. demand)
Angina pectoris can precipitate
Ischemia
Why must we be mindful of volume depletion in anemic patients?
The O2 supply for anemic patients is already low, so any other disturbance to blood supply will mess up the supply vs. demand balance.
When imbalance that causes angina pectoris is extreme, what may happen?
Congestive heart failure (CHF)
Electrical instability/ cardiac dysrhythmias (may precipitate IHD)
Myocardial infarction (MI)
The most common cause of myocardial ischemia?
Atherosclerosis
Retrosternal chest pain (described as pressure or heaviness), discomfort typically radiates to the neck, left shoulder, left arm, or lower jaw
Angina pectoris
What induces angina pectoris?
Physical exertion, emotional tension, and cold weather
What is Levine’s sign?
Clutching your chest at your heart
Angina causes what changes to EKG?
ST depression and T-wave inversion
Nuclear Stress Imaging assesses coronary perfusion by:
defining vascular regions in which stress-induced coronary blood flow is limited
Gold standard of diagnosing angina pectoris?
Coronary angiography
What is coronary angiography?
Determines anatomic extent of CAD & LV function (EF)
Life style changes that can improve angina?
Smoking cessation
Maintenance of IBW
Regular exercise
Treatment of HTN
Pharmacologic treatments of angina?
Antiplatelet drugs B-blockers Calcium channel blockers ACE inhibitors Nitrates
Revascularization to treat angina?
CABG + PTCA
Nearly all MIs are caused by:
thrombotic occlusion of a coronary artery
Percentage of stenosis required to produce angina pectoris
Stenosis >70%
Rise and fall of serum cardiac enzyme markers Troponin T or I indicates:
MI within four hours of event
What lung sound might you hear during MI?
Moist rales representing CHF
Cardiac murmur during MI may reflect:
Ischemic mitral regurgitation
Treatment of MI: remember MONA
Morphine
Oxygen
Nitrates
Aspirin
Role of morphine post-MI
Reduce pain and anxiety to decrease myocardial oxygen demand
Role of O2 post-MI:
To increase supply of oxygen
Role of nitrates post-MI:
Serves to vasodilate coronary arteries to allow blood to flow past the plaque
Role of aspirin post-MI:
Thins the blood to break down platelets to get rid of remaining clot in the coronaries
Thrombolytic therapy post-MI should take place within:
30-60 minutes of arrival to hospital
What is thrombolyic therapy?
Tissue plasminogen activator
Coronary angioplasty post-MI should take place within:
1-2 hours
When you assess for murmer:
character, location, intensity, and direction of radiation
AP valves open; so murmurs heard are AP stenosis or MT insufficiency (AS, PS, MR, TR)
Systolic murmurs
Aortic stenosis, pulmonic stenosis, mitral regurgitation, and tricuspid regurgitation are examples of:
Systolic murmurs
MT valves open; so murmurs heard are MT stenosis or AP insufficiency (MS, TS, AR, PR)
Diastolic murmurs
Mitral stenosis, tricuspid stenosis, aortic regurgitation, and pulmonic regurgitation are examples of:
Diastolic murmurs
Most common with rheumatic mitral valve disease & left atrial enlargement
Atrial fibrillation
Can occur (even without ischemic heart disease) from increased myocardial O2 demand from enlarged cardiac muscle mass (hypertrophy)
Angina Pectoris
Which murmur is a sequela of Rheumatic Heart Disease?
Mitral stenosis
In mitral stenosis, decreased MV orifice causes obstruction to LV diastolic filling and increases in LA volume and pressures: this increased pressure in the LA can eventually lead to:
Pulmonary edema
In mitral stenosis, the MV area drops from a normal (4-6 cm2) area to:
<1 cm2
In the case of severe MS, transvalvular pressure is
> 10 mmHg
Stressors of mitral stenosis include:
sepsis
AF
PE
pregnancy
Mitral stenosis is characterized by:
opening snap
Normally, what treats mitral stenosis?
Diuretics
Why should you avoid tachycardia in patients with mitral stenosis?
It impairs LV filling + increases LA pressure.
Why should you avoid decreases in systemic vascular resistance in patients with mitral stenosis?
Need to avoid compensatory increase in HR because tachycardia is not tolerated
A murmur that usually due to Rheumatic fever and is almost always associated with Mitral stenosis
Mitral regurgitation
Isolated mitral regurgitation =
Acute MI
Principal pathological change caused by a decrease in forward LV systolic volume & CO:
LA volume overload
Severe MR indicates a regurgitant fraction of:
<0.6
Fraction of the stroke volume that enters LA depends on:
1) size of MV orifice
2) HR
3) pressure gradient across MV
Early treatment of mitral regurgitaiton =
MV repair
Prolapse of one or both mitral leaflets into the LA during systole with or without MR
Mitral valve prolapse
Associated with a mid-systolic click and a late systolic murmur (click-murmur syndrome)
Mitral valve prolapse
Most common form of valvular heart disease
Mitral valve prolapse
Which form of MVP is associated with connective tissue diseases?
Secondary (syndromic) form
Idiopathic disease resulting from degeneration and calcification of aortic leaflets
Aortic stenosis
More likely to occur in persons born with bicuspid aortic valves than with normal tricuspid valves
Aortic stenosis
Risk factors for aortic stenosis?
HTN & hypercholesterolemia
Which murmur is associated with an increased incidence of sudden death?
Aortic stenosis
Characterized by obstruction to ejection of blood into the aorta due to decreases in the area of the AV orifice which increase LV pressures to maintain forward stroke volume
Aortic stenosis
Symptoms of angina pectoris?
Angina pectoris, syncope, and dyspnea on exertion
Angina pectoris with aortic stenosis has a life expectancy of how many more years?
5 years
Syncope with aortic stenosis has a life expectancy of how many more years?
3 years
Dyspnea with aortic stenosis has a life expectancy of how many more years?
2 years
systolic ejection murmur that radiates to the neck, best heard in the aortic area (2nd right ICS)
Aortic stenosis
Treatment for aortic stenosis?
Aortic valve replacement
Results from disease of the aortic leaflets or the aortic root that distorts the leaflets, preventing their coaptation
Aortic regurgitation
Acute aortic regurgitation is caused by
infective endocarditis
Characteristic blowing murmur heard best along the right sternal border plus peripheral signs of hyperdynamic circulation
Aortic regurgitation
When do symptoms of AR emerge?
When LV dysfunction is advanced.
Treatment of Aortic regurgitation?
Aortic valve replacement
Usually functional, caused by tricuspid annular dilation secondary to dilation of the right ventricle due to Pulmonary HTN
Tricuspid regurgitation
Often accompanies Pulmonary HTN and RV volume overload due to LV failure produced by Aortic or Mitral valve disease
Tricuspid regurgitation
Most common circulatory derangement affecting 30% of adults
Systemic hypertension
Systemic hypertension affects what percentage of adults?
30%
In essential hypertension, cause:
cannot be determined
Essential hypertension accounts for what percent of HTN cases?
95%
In secondary hypertension, there is a known etiology. What percentage of all cases of HTN?
5%
Most common etiology that define secondary hypertension:
Renovascular HTN from Renal Artery Stenosis= most common
In what type of hypertension is treatment often surgical?
Secondary hypertension
Defined as acute diastolic BP increases > 130 mmHg
Hypertensive crisis
When removing patient from hypertensive crisis, what should you NOT do?
Return BP to normostasis–decrease by 20% in the first 2 hours, then additional decreases over the next 24-48 hours.
Occurs when the heart is unable to provide sufficient pump action to distribute blood flow to perfuse tissues and organs of the body
CHF
Most common cause of CHF:
Impaired myocardial contractility secondary to ischemic heart disease or cardiomyopathy
Most common form of heart failure
Left-sided heart failure
Heart failure that most commonly results from left-sided heart failure
Right-sided heart failure
The left ventricle can’t contract vigorously, indicating a pumping problem: EF < 45%
Systolic HF
The left ventricle can’t relax or fill fully, indicating a filling problem from noncompliant (stiff) ventricles. EF often normal.
Diastolic HF
Ordinary physical activity does not cause symptoms
Class I
Symptoms occur with ordinary exertion
Class II
Symptoms occur with less than ordinary exertion
Class III
Symptoms occur at rest
Class IV
Fatigue at rest or with minimal exertion indicates
CHF
Hallmark of left CHF:
pulmonary symptoms
Hallmark of right CHF:
systemic venous congestion
What is the most useful test in diagnosing CHF?
Echocardiogram
Why are opioids so beneficial in treating patient with CHF?
They inhibit adrenergic activation.
Renin converts angiotensiogen to:
Angiotensin I
Angiotensin converting enzyme converts Angiotensin I to:
Angiotensin II
ARBs work on which angiotensin receptors?
Angiotensin receptor-1
Which angiotensin receptor induces a sympathetic response?
Angiotensin receptor-1
LVH in the absence of other cardiac diseases capable of inducing LVH
Hypertrophic cardiomyopathy
Principle symptoms of hypertrophic cardiomyopathy?
Angina pectoris, fatigue or syncope, tachydysrhythmias, and heart failure
What relieves angina in patients with hypertrophic cardiomyopathy? Why?
Laying down; decreases outflow obstruction
What is the best way to diagnose hypertrophic cardiomyopathy?
Definitive endomyocardial biopsy
Pharmacological treatment of hypertrophic cardiomyopathy
Beta blockers + Ca++ channel blockers
In patients with hypertrophic cardiomyopathies, what are some things anesthetists should avoid?
Sympathetic stimulation, dehydration, or vasodilation
Characterized by LV or biventricular dilation, systolic dysfxn, and nl ventricular wall thickness
Dilated cardiomyopathy
Most common cardiomyopathy is:
Dilated cardiomyopathy
3rd most common cause of HF:
Dilated cardiomyopathy
Rare dilated form of CM arises during 3rd trimester until 5 months postpartum
Peripartum cardiomyopathy
Cardiomyopathy due to systemic illnesses that produce myocardial infiltration and severe diastolic dysfunction
Secondary CM with restrictive physiology
Principle cause of secondary cardiomyopathy with restrictive physiology?
Amyloidosis: a rare disease that occurs when a substance called amyloid builds up in your organs. Amyloid is an abnormal protein that is produced in your bone marrow and can be deposited in any tissue or organ.
A cardiomyopathy that exhibits atrial dilation, but ventricles normal in size
Secondary cardiomyopathy with restrictive physiology
In the case of secondary CM with restrictive physiology, what measure is diagnostic?
Endomyocardial biopsy
Right ventricular enlargement (hypertrophy/dilation) that may progress to right sided heart failure.
Cor Pulmonale
Common cause of Cor Pulmonale:
diseases that induce pulmonary hypertension, such as COPD
Clinical signs of this disorder include peripheral edema, dyspnea, + effort-related syncope.
Cor Pulmonale
How to diagnose Cor Pulmonale on EKG?
Peaked p-waves on leads II, III and aVF indicate P Pulmonale
In patients with Cor pulmonale, how to treat?
Decrease the workload of the right ventricle by decreasing PVR and PA pressure
Inflammation of pericardium usually caused by a viral infection
Acute Pericarditis
Diagnostics include chest pain worsening with inspiration, pericardial friction rub, and ECG changes (diffuse ST segment elevation)
Acute Pericarditis
Abnormal accumulation of fluid in the pericardial cavity. Because of the limited amount of space in the pericardial cavity, fluid accumulation leads to an increased intrapericardial pressure which can negatively affect heart function
Pericardial effusion
A pericardial effusion with enough pressure to adversely affect heart function
Cardiac tamponade
CXR = “water bottle heart” in what condition?
Cardiac tamponade
Chronic inflammation of the pericardium with thickening, scarring, and muscle tightening (contracture)
Constrictive pericarditis
The frontal plane views the electrical activity of the heart as it moves:
up, down, left, right
The horizontal plane views the electrical activity of the heart as it moves:
anteriorly + posteriorly
Represents the time from the start of atrial depolarization to the start of ventricular depolarization including delay in conduction from AV node
PR interval
Length of time of PR interval:
0.12 - 0.2 s
Which leads note R wave progression in precordial leads?
Precordial leads
Because both an approaching wave of depolarization and receding wave of repolarization generate a positive deflection on EKG:
the same electrodes that generate a positive R wave generate a positive T wave.
Encompasses the time from the beginning of ventricular depolarization to the end of ventricular repolarization
QT interval
QT interval duration devoted more to:
repolarization
QT duration proportionate to:
HR
QT interval composes what percentage of the cardiac cycle?
40%
P-wave is negative in what lead?
aVR
P-wave is biphasic in what lead?
III, V1
